USB: EHCI: don't refcount QHs

This patch (as1567) removes ehci-hcd's reference counting of QH
structures.  It's not necessary to refcount these things because they
always get deallocated at exactly one spot in ehci_endpoint_disable()
(except for two special QHs, ehci->async and ehci->dummy) and are
never used again.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 3 insertions, 21 deletions

diff --git a/drivers/usb/host/ehci-mem.c b/drivers/usb/host/ehci-mem.c
index 12f70c302b0b..93132d8ad360 100644
--- a/drivers/usb/host/ehci-mem.c
+++ b/drivers/usb/host/ehci-mem.c
@@ -64,10 +64,8 @@ static inline void ehci_qtd_free (struct ehci_hcd *ehci, struct ehci_qtd *qtd)
 }
 
 
-static void qh_destroy(struct ehci_qh *qh)
+static void qh_destroy(struct ehci_hcd *ehci, struct ehci_qh *qh)
 {
-        struct ehci_hcd *ehci = qh->ehci;
-
         /* clean qtds first, and know this is not linked */
         if (!list_empty (&qh->qtd_list) || qh->qh_next.ptr) {
                 ehci_dbg (ehci, "unused qh not empty!\n");
@@ -92,8 +90,6 @@ static struct ehci_qh *ehci_qh_alloc (struct ehci_hcd *ehci, gfp_t flags)
         if (!qh->hw)
                 goto fail;
         memset(qh->hw, 0, sizeof *qh->hw);
-        qh->refcount = 1;
-        qh->ehci = ehci;
         qh->qh_dma = dma;
         // INIT_LIST_HEAD (&qh->qh_list);
         INIT_LIST_HEAD (&qh->qtd_list);
@@ -113,20 +109,6 @@ fail:
         return NULL;
 }
 
-/* to share a qh (cpu threads, or hc) */
-static inline struct ehci_qh *qh_get (struct ehci_qh *qh)
-{
-        WARN_ON(!qh->refcount);
-        qh->refcount++;
-        return qh;
-}
-
-static inline void qh_put (struct ehci_qh *qh)
-{
-        if (!--qh->refcount)
-                qh_destroy(qh);
-}
-
 /*-------------------------------------------------------------------------*/
 
 /* The queue heads and transfer descriptors are managed from pools tied
@@ -138,11 +120,11 @@ static void ehci_mem_cleanup (struct ehci_hcd *ehci)
 {
         free_cached_lists(ehci);
         if (ehci->async)
-                qh_put (ehci->async);
+                qh_destroy(ehci, ehci->async);
         ehci->async = NULL;
 
         if (ehci->dummy)
-                qh_put(ehci->dummy);
+                qh_destroy(ehci, ehci->dummy);
         ehci->dummy = NULL;
 
         /* DMA consistent memory and pools */